The present invention relates generally to commercial cooking apparatus and, in particular relates to a staged rotisserie for cooking meat products, such as poultry.
In the general field of industrial cooking and baking, numerous processes and techniques are employed. For example, it is known to process some products using batch cooking operations in which a number of products are placed in an oven, cooked for a time, and then removed, after which a subsequent batch of products is placed in the oven for cooking and the process repeats.
It is also known in industrial food processing and cooking to process foods as they are moved along a conveyor line in a rather continuous fashion. For example, cookies are often cooked this way by placing raw cookie dough on a conveyor and conveying the cookie dough through an oven chamber at a predetermined speed to have the cookie dough resident in the oven chamber for a predetermined length of time in order to bake the cookies adequately. This results in baked cookies exiting the downstream end of the oven ready for packaging.
In the processed meat trade, there is known U.S. Pat. No. 4,644,857 to Buller-Colthurst, which relates to a food processing chamber and technique for the processing of meat and poultry products. The ""857 patent describes a process chamber that is operated in a batch mode such that a batch of products can be introduced into a zone and then simply left stationary during its processing time in that zone. Once that time is up, the batch then can be moved to the next zone and simply left to stand in the next zone, and so on. The ""857 patent further describes that in order to move batches or units of products through the zones, a step-wise or batch conveyor system is provided.
In the common manner of cooking chicken or other poultry in a restaurant, a rotisserie is used in which poultry are placed on skewers or spits, and the spits are placed within a small oven. The individual spits are rotated about their axis and the group of spits revolve around a central axis to provide even cooking of all of the poultry in the rotisserie. Such a system is shown generally in U.S. Pat. No. 5,471,915 to Lopata. Unfortunately, such a system generally fails to control the residence time of each individual poultry item. Indeed, unless all the poultry items are placed in the rotisserie at the same time and later removed all at once, some poultry items can be cooked for too long, other poultry items can be cooked just the right length of time, while still other poultry items can be cooked not long enough. This is very important inasmuch as even slight undercooking of poultry can pose a serious health risk to consumers by virtue of a failure to completely kill all bacteria that might be present on or in the poultry. Moreover, even slight overcooking of the poultry is highly undesirable as it tends to make the poultry rather tough and dry, because poultry tends to be particularly sensitive to overcooking.
Accordingly, it can be seen that a need yet remains for a rotisserie for cooking food items such as poultry, which rotisserie ensures precise control over the cooking of the meat therein to ensure proper doneness of the meat. It is to the provision of such a rotisserie that the present invention is primarily directed.
Briefly described, the present invention comprises a staged rotisserie for the controlled cooking of meat, such as poultry. The novel staged rotisserie includes a frame or a housing having an inlet end and an outlet end and has a plurality of discrete heating stations arranged sequentially from the inlet end to the outlet end. The staged rotisserie further includes a number of spits for supporting meat products mounted thereon and support means for supporting the spits in the plurality of discrete heating stations. Further, driving means are provided for driving the spits in rotation and advancement means are provided for periodically advancing the spits from one of the discrete heating stations to a sequentially next one of the discrete heating stations.
As spits move toward the outlet end, the spits can be continuously rotated by the driving means. Also, the driving means can be in the form of an endless drive chain driven continuously and engaging sprockets mounted on the spits. Additionally, the staged rotisserie includes an inlet control means for controlling admission of the spits adjacent the inlet end of the housing and being operative to admit a leading spit from a queue of spits adjacent the inlet end. The inlet control means can be activated by operation of the advancement means so that as the spits are advanced, another spit can be admitted through the inlet end.
The progression of the spits through the plurality of discrete heating stations can be in a generally descending manner. The advancement means can be operable to lift the spits from a lowered cooking position to a raised advancement position from which the spits can descend by gravity to the next sequential discrete heating station. The advancement means can take the form of a series of lifters, each being operative for lifting a spit, and a cam bar for raising and lowering the lifters. Also, guides can be positioned at each of the discrete heating stations to guide movement of the spits from the lowered cooking position to the raised advancement position.
In an alternative form, a walking beam assembly is utilized to advance the spits to the next sequential position, wherein a walking beam on each side of the staged rotisserie is driven in a generally rotational direction. A series of spit rests are carried along the longitudinal length of each walking beam for lifting the ends of each spit, wherein the spits travel in a generally circular direction to the next cooking position. The walking beam assembly can be driven by a motor and a series of pivot arms. Alternatively, the walking beam assembly can be driven by a vertical and a horizontal pneumatic cylinder. As an additional alternative means, a motor driven sprocket chained linked to another sprocket and coupled to crank arms are utilized to drive the walking beam assembly. As a further alternative means, the walking beam assembly can be driven by a set of motor driven links and crank arms. These alternative means for advancing the spits allows the present invention to be utilized on almost any degree of inclination.
The invention just described has numerous advantages. For example, the invention eliminates the requirement of an operator to monitor the time that a bird spends in a cooking apparatus or to monitor the internal temperature of the meat. In this way, human error is avoided. Moreover, the invention provides an extremely uniformly cooked product and does so at relatively high volumes (large numbers of poultry can be cooked in this way). The staged rotisserie apparatus also takes up a relatively small amount of space relative to its output of poultry. The staged rotisserie has the ability to vary the cooking temperature at various stages of cooking to effect optimum cooking results. Also, the staged rotisserie is designed to minimize cooking flare-ups and preferably includes side windows and top windows to allow operators and customers to view the cooking birds directly to verify the quality of the cooking period. Importantly, by eliminating the human element in timing the cooking operation or in monitoring an internal cooking temperature in the meat, overcooked and undercooked chicken can be virtually eliminated. The apparatus, because it requires less monitoring, also increases throughput while reducing the number of personnel required to operate the equipment.
Accordingly, it is an object of the present invention to provide a rotisserie which reliably cooks poultry to a precise degree of doneness.
It is another object of the present invention to provide a rotisserie which eliminates the need to have an operator monitor how long the item is being cooked or the final temperature of the item being cooked.
It is another object of the present invention to provide a rotisserie which allows the cooking temperature at various stages of cooking to be varied.
It is another object of the present invention to provide a rotisserie which minimizes flame flare-ups.
It is another object of the present invention to provide a rotisserie which is capable of producing extremely high volumes of uniformly cooked poultry.
It is another object of the present invention to provide a poultry rotisserie requiring a minimum amount of floor space.
It is another object of the present invention to provide a rotisserie which allows the customer or operator to visually observe the entirety of the cooking operations.
It is another object of the present invention to provide a staged rotisserie that can be utilized on level, inclined or declined surfaces.
It is yet a further object of the present invention to provide a staged rotisserie which is simple in its construction, economical to manufacture, and straight forward in use.
These and other objects, features and advantages of the present invention will become more apparent to those skilled in the art upon reading the following specification in conjunction with the accompanying drawing figures.